Determination of continuous system transfer functions from sampled pulse response data

A method for determining the transfer function of a continuous system from sampled responses to single- and multiple-pulse excitation is presented. The method is an extension of the sampled-edge-response method pioneered by the theoretical work of A. Papoulis in 1962 and the application of the theory to optical systems by B. Tatian in 1965. Occasions arise when pulse rather than step-function stimuli are available for system excitations. In such cases, the method presented is useful for determining the system transfer function. The use of antialiasing filters and estimation of non-bandwidth-limited transfer functions are discussed. Practical application of the method to characterizing the system transfer function of a commercial 8- to 12-μm infrared imager is also presented.